According to the Wayback Machine no, but the Grim Dawn forum thread linked to above confirms that (a) it did work on XP; (b) the Steam version still works and (c) the developers had no intention of withdrawing XP support.

I also didn't "purchase" Grim Dawn through GOG but received a gift code as a Kickstarter backer so never saw the need to review the gamecard.
I'd broadly agree (though WinXP receiving no further updates means the support cost should be marginal compared to, say, Win10 with its Creator and Anniversary updates). However this is a case of support being inhibited by a third-party component (galaxy.dll) and while I don't expect GOG to revert to supporting WinXP with Galaxy, I do feel it is reasonable to have a workaround such as a "fixed" game executable that doesn't require galaxy.dll or a dummy version of galaxy.dll that requires (and supplies) no real functionality.

(Edit: I did try removing galaxy.dll but Grim Dawn then crashed with a message about the missing DLL, copying in an older version of galaxy.dll from Pillars of Eternity caused GD to crash with an invalid entry point error).
Hopefully by then, Linux (or some other form of Unix) should have overcome the downsides I note later.
Then please excuse my thread necromancy, but it did/does seem more appropriate to post a follow-up here than to create a new thread with a similar title.
There's very little (and I would argue almost nothing of significance) that later versions of DirectX offer feature-wise (variable softness shadows? new forms of anti-aliasing?) aside from tesselation and that, for various reasons, can't be used with anything the player may interact with so tends to be limited to cut-scenes or very distant objects.

With regard to OpenGL, the latest stable release is 4.6 and I have version 4.3 on my system, so unlikely to be a big difference.
Given that 64-bit Windows has a variety of its own issues (Patchguard hobbling security software, the requirement for separate Program Files folders for 32- and 64-bit code, storing 64-bit system code under Windows\System32\ and 32-bit equivalents under Windows\SYSWOW64, inability to handle 16-bit executables, inability to load unsigned drivers) I'm quite happy to stay with 32-bit.
Grim Dawn was funded in May 2012 over a year before XP's end of support, which is when Crate pledged Windows support and a DRM-free release. The wait for a full release has been prolonged, but backers shouldn't suffer any negative consequence for that.
I remain with XP because I prefer it - it runs the software I have purchased over the last 20 years, including nearly a thousand games.
If you researched rather than imagined, you'd have found that, with the possible exception of Tiny Firewall, System Safety Monitor (SSM) is one of the most fully featured security utilities for the Windows platform allowing control of what programs can run (optionally restricting programs further by checking parameters, essential for "programs that run programs" like cmd.exe, javaw.exe or rundll32.exe), what drivers can load, what hooks can be set, what registry entries can be modified and whether to allow a process low-level keyboard, disk or physical memory access.

As long as it is installed on a clean system and configured properly, there is no realistic way for malware to bypass it. It does depend on the user making the right choices to its prompts, so would be of no use to those who just click on Allow/Install/Screw Me by default.

It is no longer commercially available (and ditto for Process Guard) which is a crying shame (the diligent should be able to find a copy of SSM and a "Valued Customer" key offered by SysSafety before they closed), but unlike anti-virus software with its need for constant signature updates, it doesn't require support to maintain its effectiveness (unless the OS changes).
Because Linux doesn't have anything like SSM (the closest would be AppArmor but that requires profiles to be created in advance).

Because Linux doesn't have a "decent" firewall that can control access on a per-process/program basis (the closest would be the likes of Douane or TuxGuardian, but they only allow/deny per application and cannot restrict an application to specific ports or IP addresses/domain names). Since I use Tor for web access, I like to be able to block my browser from direct (port 80, 443) access to ensure that any "Tor-bypass" tricks are prevented.

Because Linux doesn't have drivers for all the hardware I own (this applies to Win10 also).

Of course, things will likely improve and I periodically check, but for now Linux is a no-go for me.

Question: What's this? (Comes default with every Redhat based product, including Fedora.)

Okay, do you want your tinfoil with chicken grease or pizza grease? The reason there aren't madhouse firewall suites is because most Linux distros are rolled with the tools you need to make the internet exactly as restrictive, chafing and uncomfortable as you want. I even have a firewall application on my stock xfce install that's not doing anything. You'd probably just want firewall-config, shorewall, or whatever you fancy. (There's an entire application group for such an occasion.)

Really? What hardware might that be? If it's something like a crackly old osollioscope from 1947 or a punch card drive, I can't say I'm not suprised.

SELinux, if you had bothered to read its documentation, requires policy files to be created for each process in advance, much like AppArmor. You cannot run a program and receive prompts on whether to allow or deny certain activities when they happen, which is the functionality that SSM offers.

Also, in Redhat's case, only processes that run as root or listen to a port (and therefore receive unsolicited traffic) are restricted. Anything else is unrestricted and unaffected by SELinux.
Wakey, wakey - virtually every piece of malware written over the last 15 years requires Internet access to function (remote access trojans have to connect to a command centre as does spyware and DDoS tools, ransomware needs to connect to a server to leave its decryption key). Keeping a tight lid on Internet access is critical for a secure system since not only do you reduce the likelihood of being compromised in the first place, but you also improve the chance of detecting any successful compromise (when a new process requests Internet access or tries to modify another application with Internet access). Edit: this also helps in preventing phone home behaviour, ironically also a Galaxy feature.
That's your choice - but don't presume to offer security advice to anyone if you're not taking it seriously yourself.
No I would most certainly not. The examples you list are just GUIs for netfilter/iptables and do not add the capabilities I require (specifically the ability to restrict network access on a per-process basis). They don't even have the capability of Windows Firewall, let alone the more sophisticated firewall software available on Windows like Look'n'Stop, Jetico or Agnitum Outpost (which also include control of inter-process communication - DLL injection, code injection, OLE, DDE, pipes, etc).
I'm not going to go into details because this is a thread about GOG's Galaxy preventing software from running on Windows XP, not a Linux advocacy thread.

I would therefore ask that any further follow-up remains on-topic. Thank you for your participation and co-operation.

it is nice that you like to use a dead OS, and you may have many reasons why you personally do so. I still like AmigaOS and think it has many benefits still over Windows. But using it or not is completely your own choice, and when you make that choice you do need to take in consideration that if you want to use a OS which have been phased out, then the onus is on you to make software run on it or not. A company can not be expected to support a OS which is no longer supported.

The point being made in this thread is that companies are still supporting WinXP - Crate Entertainment's system requirements still list it. However GOG's supposedly optional Galaxy is now blocking it, which is going to affect an increasing number of games.

Fine, sure. But let me put it this way: I feel the only reason you need to use that entire suite of software is because you're using a nearly 20 year old operating system. (For reasons which I have failed to ascertain.) If you dragged yourself, kicking and screaming to something newer, you'd find that it'd be entire unnecessary.

In all my years online, I've never had to worry about things like Phishing, DDOS, Ransomware, Bonsy Buddy, or spyware. I'm not sure what you do in your spare time that has you worrying about such things in the first place, but I've found that if you browse sanely, you'll never give a single thought to such worries, and I've been browsing happily since 1998ish, so things like worms, viruses, and crackers have been an actual concept.

I stopped using Spybot S&D back in the mid 2000s, and any mainline antivirus aside from WSE/Defender quite some time ago too.

and that's nice by them, but it is those companies choice. at some point they will also stop doing so, as it will just be to costly to maintain it (the user base on XP is very small, and getting smaller). also the argument "some companies do so" is not very good, as there is also many (much more today) that no longer supports XP.

Crate may offer XP support, gOg does not (and does not list it). Therefore, if you want Grim Dawn on XP, you need to go to Crate and / or get it from a different supplier that still offers XP support.

As a sidenote, AmigaOS is slightly less dead than Windows XP, the last update it had was in 2016, and there's a linage of continuation, such as Haiku. XP is a dead end due to the kernel version and other flaws. (Surprisingly, systems like OpenVMS are happily continuing.)

ohh, and as a side-note, in the other store, Create says Grim Dawn (the base game) is supported on XP, but the expansions are not.... too me it feels more like forgetting to update store pages more than an actual commitment.

edit - and it seems the other store will stop XP support completely January 2019

https://support.steampowered.com/kb_article.php?ref=1558-AFCM-4577

Approaching Crate is an option, but since GOG "broke" Grim Dawn, GOG should be the ones to "fix" it.
If you remember Bonzi Buddy then you must have been online for nearly 20 years.

Are you really trying to say that the malware threat has decreased since then?

Yes. Absolutely. Not only are there less overall viruses being written (with cracker/hacker culture having mellowed out), but exploits are now able to be nailed the instant they're noticed, and many programs have sanity checks built into them to prevent malicious behavior. Technologies are implemented to prevent malware from functioning in the first place such as ASLR, sandboxing, and basic command structures.

In the past, everything was assumed root or highest execution power, and allowed any permission it wanted.

Then I doubt that Win7 users will face anything like this. Win7 is already in the supported OS list for most games in the store (or even for all), a huge number of customers have made their decision to buy or not to buy a product based on it. Changing system requirements long time after the release may be done by developers (I've seen patches like that) but doubtfully by GOG. And on GOG patches are optional so existing customers may ignore such patches from developers.

no, gOg is delivering exactly what they promise. it is only Cave who offers XP support.

Is it support or is compatible?

I believe some measure of fairness should prevail.
If a GOG user purchases a game that indicates on the store page as being compatible with a certain OS, then it is reasonable to expect that future DL access to said game will remain so. Since GOG sells digital access to their games as a continuing concern rather than a once-off DL, the expectation that game access sold at one time as compatible for a particular OS should remain in the future, but no guarantees are made on future updates of course.

The moment the game gets updated beyond support for these previous advertised compatible OSes, the older (offline, non-Galaxy) installers should be made permanently available on the DL page, appropriately tagged for identification. Then they may continue to provide newer updates that keep the game compatible with newer OSes. This would be perfectly acceptable, as really old games (particularly SP) will rarely need updates for antiquated OSes. This of course not suit older multiplayer games, where future version changes made to the remaining compatible OSes shrink potential player bases for older installation customers. That unfortunately is inevitable, as time passes.